Yes, there are quite a few. You can start by looking on fanfiction platforms like Archive of Our Own. Some fanfics might focus on their adventures during their school days at Hogwarts, exploring their deep friendship and the bond they share as if they were twins in a sense. They might get into all sorts of mischief together, just like in the original Harry Potter stories.
Well, it's the combination of their personalities. James was brave and a bit of a prankster, and Sirius was rebellious. When they are like twins in fanfics, their adventures together become more exciting. We get to see how they handle different situations as a unit, whether it's dealing with Slytherins or facing the dark arts. Also, it's about exploring their backstories more deeply. Maybe there are secrets about their families that are revealed when they are thought of as twins.
One great 'James Potter and Sirius Black fanfic' to start with is 'Prongsfoot: The Marauders' Era'. It really captures their friendship well and has a lot of interesting plotlines that are true to the characters' personalities in the original series.
There is a fanfic where James Sirius Potter discovers a hidden mystery in Hogwarts. In this story, he teams up with some new friends. The author does a wonderful job of creating a believable world and the relationships between the characters are really well - written. It's a great read if you want to explore more about this character.
Friendship is a very common theme. The deep bond between Sirius and James is often explored, like how they were always there for each other, through pranks, study sessions, and dealing with the Slytherins. Another theme is loyalty. Their loyalty to each other and to their group, the Marauders, is a central part of many stories.
Friendship is a very common theme. Their bond as best friends is often explored, showing how they supported each other through thick and thin at Hogwarts.
Another place to find 'james sirius potter fanfic' is Tumblr. There are many fanfic writers who post their works or snippets of their works on their Tumblr blogs. You can search for relevant tags like #james sirius potter fanfic or #james sirius potter. However, the search on Tumblr can be a bit more scattered compared to dedicated fanfic sites.
One common theme is friendship. Their bond is often explored in depth, showing how they were like brothers. Another theme is mischief, as they were known for their pranks at Hogwarts. For example, in many fanfics, they play elaborate pranks on Snape.
One great 'james sirius potter fanfic' is 'The Next Generation's Adventures'. It shows James Sirius Potter in his Hogwarts years, dealing with the legacy of his famous family. He forms a new club for students interested in exploring the Forbidden Forest in a safe way. Another is 'James Sirius and the Lost Spell'. In this story, he stumbles upon an ancient spellbook and has to figure out how to handle the powerful magic within it without getting into too much trouble.
His father, Harry Potter, might also send a Howler. Harry knows the importance of discipline and responsibility, and if James was shirking his duties or not following the rules at Hogwarts, Harry would not hesitate to use a Howler to communicate his disappointment and expectations.